Oil filter presses have been proposed for crushing spent disposable-type oil filters commonly used on automobiles and trucks in order to reclaim residual oil from the filters before disposal. Examples of prior art oil filter presses include those disclosed in the U.S. Pat. No. 4,927,085 to Oberg, granted May 22, 1990; U.S. Pat. No. 5,060,564 to Bufford et al, granted Oct. 29, 1991; and U.S. Pat. No. 5,109,763 to Morris et al, granted May 5, 1992.
To be of practical value to small automotive service stations and oil change facilities, an oil filter press must be compact, simply constructed, low cost, and reliable. The known prior art filter presses utilize a fluid power cylinder to actuate an oil filter crushing device. Such fluid cylinders, however, are costly, complex, and often require periodic maintenance of fluid seals.
Another device disclosed in Clay, U.S. Pat. No. 3,763,773 uses an expandable bellows which is filled with water, the weight of which supplies the force necessary to compact trash. Using water filled bellows, however, would be too slow and impractical for crushing oil filters or the like where rapid, repetitive actuation is required potentially to crush relatively large numbers of oil filters.